b1: rút gọn các pân số sau
\(\dfrac{-14}{-52}\) \(\dfrac{36}{-10}\)
\(\dfrac{-35}{-156}\) \(\dfrac{-360}{480}\)
\(\dfrac{3.5}{20.33}\) \(\dfrac{-4.56}{16.32}\)
\(\dfrac{18.9.-18}{2.20}\) \(\dfrac{8.6-8.10}{16}\)
b2:tìm x thuộc z:
\(\dfrac{2}{7}\)=\(\dfrac{x}{56}\)
\(\dfrac{x}{-5}\)=\(\dfrac{36}{45}\)
\(\dfrac{42}{48}\)=\(\dfrac{-7}{x}\)
\(\dfrac{-30}{x}\)=\(\dfrac{6}{-13}\)
các bn trình bày hộ mk lun nha
Bài 1:
1,\(\dfrac{-14}{-52}\) =\(\dfrac{-14:\left(-2\right)}{-52:\left(-2\right)}\)=\(\dfrac{7}{26}\)
2,\(\dfrac{-36}{-10}\)=\(\dfrac{36:\left(-2\right)}{-10:\left(-2\right)}\)=\(\dfrac{-18}{5}\)
3,\(\dfrac{-35}{-156}\)=\(\dfrac{-35:\left(-1\right)}{-156:\left(-1\right)}\)=\(\dfrac{35}{156}\)
4,\(\dfrac{-360}{480}\)=\(\dfrac{-360:120}{480:120}\)=\(\dfrac{-3}{4}\)
5,\(\dfrac{3.5}{20.33}\)=\(\dfrac{3.5}{4.5.3.11}\)=\(\dfrac{1}{44}\)
6,\(\dfrac{-4.56}{16.32}=\dfrac{-4.7.8}{4.4.8.4}=\dfrac{-7}{16}\)
7,\(\dfrac{2.3.16}{24.21.8}=\dfrac{2.3.4.4}{6.4.7.3.2.4}=\dfrac{1}{42}\)
8,\(\dfrac{8.6-8.10}{16}=\dfrac{8.\left(6-10\right)}{8.2}=-2\)
9,\(\dfrac{18.9-18}{2-20}=\dfrac{18.\left(9-1\right)}{-18}=-8\)